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JFBE 2(2): 133-138, 2019Journal of Food and Bioprocess EngineeringJournal homepage: https://jfabe.ut.ac.irOriginal researchEffect of Lactobacillus acidophilus on the physicochemical and sensory propertiesof Aloe veraMaryam Bahramia, Seyed ziaeddin Hosseini mazharia, Zeinab Ebrahimzadeh Mousavib,*a Facultyof medical science, Islamic Azad University, Science and Research branch, Tehran, IranBio-processing and Bio-detection Lab, Department of Food science, Technology and Engineering, Faculty of Agricultural Engineeringand Technology, University of Tehran, Karaj, IranbABSTRACTNowadays, in many developed societies, consumer health awareness towards the role of food in human health andnutrition has been considerably increased. Regarding the biological role of food components on human health,consumers are interested in consuming food products with an improved functionality. Non-dairy probiotic drinksare considered as functional foods. The purpose of this study is to investigate the possibility of development ofAloe vera drink bearing probiotic Lactobacillus acidophilus. Therefore, the growth and survival of these bacteriawere investigated during 12 days at two temperatures of 4 and 25 C. The acidity, total sugar and pH of the drinksamples were measured at days 1, 6 and 12. The growth of Lactobacillus acidophilus in the drinks maintained at25 C was considerably better compared to the sample kept at 4 C. Lactobacillus acidophilus increased theacidity during cold storage (p 0.05) and less sugar intake occurred at this condition. Addition of Lactobacillusacidophilus to Aloe vera did not have a negative effect on its sensory properties and people who were willing touse probiotic Aloe vera. The results of this study showed that beverage, is a suitable medium for producing aprobiotic drink containing an acceptable level of Lactobacillus acidophilus and preferred by consumers in terms ofsensory evaluation.Keywords: Aloe vera, Probiotics, Viability, Sensory evaluationReceived 20 April 2019; Received 4 August 2019; Accepted 14 August 20191. IntroductionRecent economic and social developments have created manyproblems for human health. Excessive tension and occupation haveled to diseases such as heart attack, high blood pressure, intestinaldisorders and various types of cancers (Kun et al., 2008). One ofthe effective ways of preventing or eliminating these diseases is toconsider probiotic food products in the daily diet. The consumptionof these food products has become prevalent in developed countriessuch as Europe, the United States and Japan. More than 90probiotic products containing Lactobacillus acidophilus andBifidobacterium bifidum are produced all over the world (Granatoet al., 2010; Sohrabvandi et al., 2010). Probiotic products can bedivided into two categories: 1-probiotic dairy products such asyogurt, cheese, sour cream, buttermilk, ice cream, milk, wheydrinks and dairy desserts, 2 nondairy probiotic products such ascereals, sweets, beverages, baby food and meat products(Sohrabvandi et al., 2010; Mohammadi et al., 2012).*Corresponding author.E-mail address: zeinab.mosavi@ut.ac.ir (Z. Mousavi).Fruits and vegetable drinks with nutritional and biologicalproperties are suitable medium bearing probiotic bacteria as somefruits and vegetables contain prebiotics that stimulate the growth ofcertain probiotics. In addition, It has been shown that the beneficialeffects of fruits and vegetables can be improved by biologicalprocesses such as lactic fermentation performed by probioticbacteria. In many studies, probiotics are used in dairy products, butlactose intolerance and cholesterol levels in these products are twomain disadvantages, which have led to a limited consumption bysome group of people (Moraru et al., 2019). Therefore, the use ofprobiotics in fruit juice and vegetables can be considered as a goodalternative for the group of people with special needs (ie, plantersand people with allergic reactions to milk proteins) (Moraru et al.,2019; Krasaekoopt & Kitsawad, 2010).Therefore, fruit juice has thepotential for becoming a probiotic product for the followingreasons: its use by a wide range of people has acceptable sensoryproperties of the absence of incompatible compounds (such aslactose) (Nandi et al., 2017).According to previous studies, the main strains used in nondairy probiotic drinks are: Lactobacillus casei, bulgaricus,

Bahrami et al.JFBE 2(2): 133-138, 2019Lactobacillus acidophilus and Bifidobacterium (Granato et al.,2010; Nualkaekul & Charalampopoulos, 2011; Krasaekoopt &Kitsawad, 2010)Pereira et al. (2011) studied the fermentation of apple juiceusing Lactobacillus casei, which showed suitable survival underrefrigerated storage conditions. During fermentation and coldstorage condition, the brightness of apple juice increased and itsredness decreased.Sadaghdar et al. (2012) found that probiotic viability in foodsamples depends on pH, storage temperature, oxygen content,incubation temperature, refrigerated temperature and storage time,the presence of competitive bacteria and viruses and the deterrentdepends. Therefore, the formulation of nutrients is important in theactivity and survival of probiotics over a long period of time (Shah2007; Ding & Shah, 2009). Due to the fact that the pH of mostjuices is 3.5-3.7 (Buruleanu et al., 2009; Mohan et al., 2013) aswell as bacteria sensitive to acidic conditions, strains should beused to survive in. This condition has the health of the product andincrease its shelf life (Mousavi et al., 2011; Mohan et al., 2013) .Therefore, the addition of probiotics to fruit and vegetable baseddrinks is more complex than dairy products due to the need toprotect them against acidic conditions. The results of the Kun et al.(2008) showed that if the Bifidobacterium the carrot juice is anappropriate growth medium for Bifidobacteria. This study wascarried out using two different initial bacterial population of 10 6 cfu/mL, and. It was concluded that the inoculation of vegetable juiceor fruits with an initial concentration of 107 cfu /mL accelerated theprocess of fermentation. Liu and Lin (2000) found thatLactobacillus bulgaricus in Chile slowly grew due to its inability toferment sucrose and other soya carbohydrates, and produced a littleamount of acid.In a study conducted by Vinderola et al., (2002), it was foundthat despite of higher level of acids produced by Lactobacilluscasei, it showed a higher viability than Lactobacillusacidophilus.Therefore, it has been concluded that the Lactobacilluscasei species has suitable resistance to acidic conditions.Nevertheless, probiotics survival in fruit and vegetable foods ismore difficult than dairy products for reasons such as the acidity ofthe environment, the presence of plant antimicrobials and the lackof nutrient components required for their growth (Mohan et al.,2013; Moraru et al., 2019; Granato et al., 2010; Mousavi et al.,2011). In addition, the probability of persistence and stability ofprobiotics in dairy products such as yogurt is extensivelyinvestigated, but there is not enough information on their survivalin non-dairy products (de Almeida et al., 2008). Moreover, theaddition of probiotics to fruit juices and vegetables causes anobvious unacceptable taste of the product. Therefore, furtherstudies are needed to increase the probiotic survival capacity ofthese products and improve their sensory properties.Aloe vera belongs to the Liliaceae family, which includesvarieties of plants with different characteristics (Minjares-Fuenteset al., 2018). The most important part of the plant is Aloe vera leaf,because studies have shown that Aloe vera leaves contain essentialamino acids, vitamins B1, A, B2, B6, B12, C, E, gum Resins, uronicacid, enzymes such as oxidase and catalase minerals such ascalcium, sodium, iron, potassium, chlorine, manganese, copper andzinc, various sugars and various compounds such as alumin,anthraquinone and its derivatives, beryllium glycoside andisobarboleum essential oil, water (Hamman, 2008a; MinjaresFuentes et al., 2018). According to different researches, the Aloevera leaf gel have various healing properties, including antiinflammatory, antiviral, antibacterial and antifungal effects, woundand radiation damage and stimulation of hematopoiesis (Hamman,2008b; Rahman et al., 2017; Goudarzi et al., 2015) According toliterature review performed by the author, no investigation on theprobiotication of Aloe vera drink has been performed yet.Therefore, this study was conducted to study the survival ofLactobacillus acidophilus in Aloe vera drink and its effect onphysicochemical properties and sensory properties of the drink.2. Material and Methods2.1. Culture preparationThe bacteria Lactobacillus acidophilus was purchased from theChristian Hansen Co. in Denmark. Bacterial culture was storedfrozen at -20 ºC in MRS medium (Merck, Germany) containing20% glycerol. The inoculated drink was incubated at 37 for 24 hunder anaerobic conditions using gas type C in an anaerobic jar.Viable cells were determined at intervals of the first, sixth andtwelfth days, by the standard plate count method using MRS agarmedium and the results were expressed as colony-forming units permilliliter of sample (CFU/mL).2.2. Drink preparationAloe vera leaves were bought from the local market in Tehran.Weighted, rinsed with tap water and disinfectant. Then, the skinwas peeled off and the gel was extracted. The extracted gel (40 mL)was homogenized by a mixer, then, pasteurized at 70 C for 30min. After cooling the gel to 5 C under vacuum conditionprovided by a rotary evaporator (Büchi, Switzerland), 60 mL ofpreviously prepared syrup (30 g sugar in 70 mL: distilled waterpasturized at 80 C for 30 min) was added to it. Then 0.5% w/vCitric Acid (Merck, Germany), 0.3 %w/v Ascorbic acid, wereadded to the mixture.2.3. Chemical analysis2.3.1. pH measurementThe pH of the samples was measured by a digital pH meter(Jenway, Germany), previously calibrated with Buffer 4 and 7.2.3.2. Acidity measurementsA digital pH meter (Metrohm 744, Netherland) was used forthe pH measurements. Total titrable acidity, expressed as citric acidpercentage, was determined by the sample with titrazol 0.1 N(Merck, Germany) to pH 8.2. Eventually, the titratable acidity wasreported as g citric acid/100 g sample using following equation:A m 0.064 100w(1)where, A was Titratable acidity (g citric acid/100 g of sample), mwas mL used titrazol 0.1 N and w was weight of sample.2.3.3. Sugar measurement134